If header of inner loop is aligned, do not align the outer loop header. We don't want to add nops in the outer loop for the sake of aligning the inner loop.

llvm-svn: 71609

1 files changed, 45 insertions, 0 deletions

diff --git a/llvm/test/CodeGen/X86/avoid-loop-align-2.ll b/llvm/test/CodeGen/X86/avoid-loop-align-2.ll
new file mode 100644
index 00000000000..9f0aeb32c41
--- /dev/null
+++ b/llvm/test/CodeGen/X86/avoid-loop-align-2.ll
@@ -0,0 +1,45 @@
+; RUN: llvm-as < %s | llc -march=x86 | grep align | count 3
+
+@x = external global i32*		; <i32**> [#uses=1]
+
+define i32 @t(i32 %a, i32 %b) nounwind readonly ssp {
+entry:
+	%0 = icmp eq i32 %a, 0		; <i1> [#uses=1]
+	br i1 %0, label %bb5, label %bb.nph12
+
+bb.nph12:		; preds = %entry
+	%1 = icmp eq i32 %b, 0		; <i1> [#uses=1]
+	%2 = load i32** @x, align 8		; <i32*> [#uses=1]
+	br i1 %1, label %bb2.preheader, label %bb2.preheader.us
+
+bb2.preheader.us:		; preds = %bb2.bb3_crit_edge.us, %bb.nph12
+	%indvar18 = phi i32 [ 0, %bb.nph12 ], [ %indvar.next19, %bb2.bb3_crit_edge.us ]		; <i32> [#uses=2]
+	%sum.111.us = phi i32 [ 0, %bb.nph12 ], [ %4, %bb2.bb3_crit_edge.us ]		; <i32> [#uses=0]
+	%tmp16 = mul i32 %indvar18, %a		; <i32> [#uses=1]
+	br label %bb1.us
+
+bb1.us:		; preds = %bb1.us, %bb2.preheader.us
+	%indvar = phi i32 [ 0, %bb2.preheader.us ], [ %indvar.next, %bb1.us ]		; <i32> [#uses=2]
+	%tmp17 = add i32 %indvar, %tmp16		; <i32> [#uses=1]
+	%tmp. = zext i32 %tmp17 to i64		; <i64> [#uses=1]
+	%3 = getelementptr i32* %2, i64 %tmp.		; <i32*> [#uses=1]
+	%4 = load i32* %3, align 4		; <i32> [#uses=2]
+	%indvar.next = add i32 %indvar, 1		; <i32> [#uses=2]
+	%exitcond = icmp eq i32 %indvar.next, %b		; <i1> [#uses=1]
+	br i1 %exitcond, label %bb2.bb3_crit_edge.us, label %bb1.us
+
+bb2.bb3_crit_edge.us:		; preds = %bb1.us
+	%indvar.next19 = add i32 %indvar18, 1		; <i32> [#uses=2]
+	%exitcond22 = icmp eq i32 %indvar.next19, %a		; <i1> [#uses=1]
+	br i1 %exitcond22, label %bb5, label %bb2.preheader.us
+
+bb2.preheader:		; preds = %bb2.preheader, %bb.nph12
+	%indvar24 = phi i32 [ %indvar.next25, %bb2.preheader ], [ 0, %bb.nph12 ]		; <i32> [#uses=1]
+	%indvar.next25 = add i32 %indvar24, 1		; <i32> [#uses=2]
+	%exitcond28 = icmp eq i32 %indvar.next25, %a		; <i1> [#uses=1]
+	br i1 %exitcond28, label %bb5, label %bb2.preheader
+
+bb5:		; preds = %bb2.preheader, %bb2.bb3_crit_edge.us, %entry
+	%sum.1.lcssa = phi i32 [ 0, %entry ], [ 0, %bb2.preheader ], [ %4, %bb2.bb3_crit_edge.us ]		; <i32> [#uses=1]
+	ret i32 %sum.1.lcssa
+}